All-Payer Analysis of Heart Failure Hospitalization 30-Day Readmission: Comorbidities Matter

Background Thirty-day readmission following heart failure hospitalization impacts hospital performance measures and reimbursement. We investigated readmission characteristics and the magnitude of 30-day hospital readmissions after hospital discharge for heart failure using the Healthcare Cost and Utilization Project State Inpatient Databases (SID). Methods Adults aged ≥ 40 years hospitalized with a primary discharge diagnosis of heart failure from 2007-2011 were identified in the California, New York, and Florida SIDs. Characteristics of patients with and without 7-, 8 to 30-, and 30-day readmission, and primary readmission diagnoses and risk factors for readmission were examined. Results We identified 547,068 patients with mean age 74.7 years; 50.7% were female, and 65.4% were White. Of 117,123 patients (21.4%) readmitted within 30 days (median 12 days), 69.7% had a non-heart failure primary readmission diagnosis. Patients with 30-day readmissions more frequently had a history of previous admission with heart failure as a secondary diagnosis, fluid and electrolyte disorders, and chronic deficiency anemia. There were no significant clinical differences at baseline between those patients whose first readmission was in the first 7 days after discharge vs in the next 23 days. The most common primary diagnoses for 30-day non-heart failure readmissions were other cardiovascular conditions (14.9%), pulmonary disease (8.5%), and infections (7.7%). Conclusions In this large all-payer cohort, ∼70% of 30-day readmissions were for non-heart failure causes, and the median time to readmission was 12 days. Future interventions to reduce readmissions should focus on common comorbid conditions that contribute to readmission burden.